The Torque Teno Virus Titer in Saliva Reflects the Level of Circulating CD4+ T Lymphocytes and HIV in Individuals Undergoing Antiretroviral Maintenance Therapy

IntroductionTorque teno virus (TTV) is a non-pathogenic virus present in body fluids. Its titer in the circulation increases in association with immune suppression, such as in HIV-infected individuals. We evaluated if the TTV titer in saliva from HIV-positive individuals undergoing antiretroviral therapy (ART) was related to the circulating CD4+ T lymphocyte concentration and the HIV titer.MethodsSaliva was collected from 276 asymptomatic individuals undergoing ART, and an additional 48 individuals positive for AIDS-associated Kaposi's Sarcoma (AIDS-KS). The salivary TTV titer was measured by gene amplification analysis. The circulating CD4+ T lymphocyte and HIV levels were obtained by chart review.ResultsTTV was detectable in saliva from 80% of the asymptomatic subjects and 87% of those with AIDS-KS. In the asymptomatic group the median log10 TTV titer/ml was 3.3 in 200 males vs. 2.4 in 76 females (p < 0.0001). TTV titer/ml was 3.7 when HIV was acquired by intravenous drug usage, 3.2 when by sexual acquisition and 2.4 when blood transfusion acquired. The salivary TTV titer was inversely correlated with the circulating CD4+ T lymphocyte level (p < 0.0001) and positively correlated with the circulating HIV concentration (p = 0.0005). The median salivary TTV titer and circulating HIV titer were higher, and the CD4+ count was lower, in individuals positive for AIDS-KS than in the asymptomatic subjects (p < 0.0001).ConclusionThe TTV titer in saliva is a potential biomarker for monitoring immune status in individuals undergoing ART.

Biosafety of human environments can be supported by effective use of renewable biomass

Preventing pathogenic viral and bacterial transmission in the human environment is critical, especially in potential outbreaks that may be caused by the release of ancient bacteria currently trapped in the permafrost. Existing commercial disinfectants present issues such as a high carbon footprint. This study proposes a sustainable alternative, a bioliquid derived from biomass prepared by hydrothermal liquefaction. Results indicate a high inactivation rate of pathogenic virus and bacteria by the as-prepared bioliquid, such as up to 99.99% for H1N1, H5N1, H7N9 influenza A virus, and Bacillus subtilis var. niger spores and 99.49% for Bacillus anthracis. Inactivation of Escherichia coli and Staphylococcus epidermidis confirmed that low-molecular-weight and low-polarity compounds in bioliquid are potential antibacterial components. High temperatures promoted the production of antibacterial substances via depolymerization and dehydration reactions. Moreover, bioliquid was innoxious as confirmed by the rabbit skin test, and the cost per kilogram of the bioliquid was $0.04427, which is notably lower than that of commercial disinfectants. This study demonstrates the potential of biomass to support our biosafety with greater environmental sustainability.

A Functional Minigenome of Parvovirus B19

Parvovirus B19 (B19V) is a human pathogenic virus of clinical relevance, characterized by a selective tropism for erythroid progenitor cells in bone marrow. Relevant information on viral characteristics and lifecycle can be obtained from experiments involving engineered genetic systems in appropriate in vitro cellular models. Previously, a B19V genome of defined consensus sequence was designed, synthesized and cloned in a complete and functional form, able to replicate and produce infectious viral particles in a producer/amplifier cell system. Based on such a system, we have now designed and produced a derived B19V minigenome, reduced to a replicon unit. The genome terminal regions were maintained in a form able to sustain viral replication, while the internal region was clipped to include only the left-side genetic set, containing the coding sequence for the functional NS1 protein. Following transfection in UT7/EpoS1 cells, this minigenome still proved competent for replication, transcription and production of NS1 protein. Further, the B19V minigenome was able to complement B19-derived, NS1-defective genomes, restoring their ability to express viral capsid proteins. The B19V genome was thus engineered to yield a two-component system, with complementing functions, providing a valuable tool for studying viral expression and genetics, suitable to further engineering for purposes of translational research.

Development of an Indirect ELISA Based on Spike Protein to Detect Antibodies against Feline Coronavirus

Feline coronavirus (FCoV) is a pathogenic virus commonly found in cats that causes a benign enteric illness and fatal systemic disease, feline infectious peritonitis. The development of serological diagnostic tools for FCoV is helpful for clinical diagnosis and epidemiological investigation. Therefore, this study aimed to develop an indirect enzyme-linked immunosorbent assay (iELISA) to detect antibodies against FCoV using histidine-tagged recombinant spike protein. FCoV S protein (1127–1400 aa) was expressed and used as an antigen to establish an ELISA. Mice and rabbits immunized with the protein produced antibodies that were recognized and bound to the protein. The intra-assay coefficient of variation (CV) was 1.15–5.04% and the inter-assay CV was 4.28–15.13%, suggesting an acceptable repeatability. iELISA did not cross-react with antisera against other feline viruses. The receiver operating characteristic curve analysis revealed an 86.7% sensitivity and 93.3% specificity for iELISA. Serum samples (n = 107) were tested for anti-FCoV antibodies, and 70.09% of samples were positive for antibodies against FCoV. The iELISA developed in our study can be used to measure serum FCoV antibodies due to its acceptable repeatability, sensitivity, and specificity. Additionally, field sample analysis data demonstrated that FCoV is highly prevalent in cat populations in Fujian province, China.

The Oncolytic Caprine Herpesvirus 1 (CpHV-1) Induces Apoptosis and Synergizes with Cisplatin in Mesothelioma Cell Lines: A New Potential Virotherapy Approach

Malignant mesothelioma (MM) is an aggressive asbestos-related cancer, against which no curative modalities exist. Oncolytic virotherapy is a promising therapeutic approach, for which MM is an ideal candidate; indeed, the pleural location provides direct access for the intra-tumoral injection of oncolytic viruses (OVs). Some non-human OVs offer advantages over human OVs, including the non-pathogenicity in humans and the absence of pre-existing immunity. We previously showed that caprine herpesvirus 1 (CpHV-1), a non-pathogenic virus for humans, can kill different human cancer cell lines. Here, we assessed CpHV-1 effects on MM (NCI-H28, MSTO, NCI-H2052) and non-tumor mesothelial (MET-5A) cells. We found that CpHV-1 reduced cell viability and clonogenic potential in all MM cell lines without affecting non-tumor cells, in which, indeed, we did not detect intracellular viral DNA after treatment. In particular, CpHV-1 induced MM cell apoptosis and accumulation in G0/G1 or S cell cycle phases. Moreover, CpHV-1 strongly synergized with cisplatin, the drug currently used in MM chemotherapy, and this agent combination did not affect normal mesothelial cells. Although further studies are required to elucidate the mechanisms underlying the selective CpHV-1 action on MM cells, our data suggest that the CpHV-1-cisplatin combination could be a feasible strategy against MM.

Propagation of SARS-CoV-2 in Calu-3 Cells to Eliminate Mutations in the Furin Cleavage Site of Spike

SARS-CoV-2 pathogenesis, vaccine, and therapeutic studies rely on the use of animals challenged with highly pathogenic virus stocks produced in cell cultures. Ideally, these virus stocks should be genetically and functionally similar to the original clinical isolate, retaining wild-type properties to be reliably used in animal model studies. It is well-established that SARS-CoV-2 isolates serially passaged on Vero cell lines accumulate mutations and deletions in the furin cleavage site; however, these can be eliminated when passaged on Calu-3 lung epithelial cell lines, as presented in this study. As numerous stocks of SARS-CoV-2 variants of concern are being grown in cell cultures with the intent for use in animal models, it is essential that propagation methods generate virus stocks that are pathogenic in vivo. Here, we found that the propagation of a B.1.351 SARS-CoV-2 stock on Calu-3 cells eliminated viruses that previously accumulated mutations in the furin cleavage site. Notably, there were alternative variants that accumulated at the same nucleotide positions in virus populations grown on Calu-3 cells at multiple independent facilities. When a Calu-3-derived B.1.351 virus stock was used to infect hamsters, the virus remained pathogenic and the Calu-3-specific variants persisted in the population. These results suggest that Calu-3-derived virus stocks are pathogenic but care should still be taken to evaluate virus stocks for newly arising mutations during propagation.

Interrelation of global changes in the planet's biosphere with the expansion of viruses and the COVID-19 pandemic

Epidemics of new, previously unknown human viral diseases have been occurring with increasing frequency in recent decades. The COVID-19 pandemic caused by the SARS-CoV-2 coronavirus has demonstrated humanity's unpreparedness for new challenges and a complete lack of understanding of the causes of viral aggression. An attempt to explain the catastrophic development of the pandemic by accidental transmission of the virus from an animal to a person does not seem convincing. The explosive development of the epidemic process in large ecosystems negates the existing ideas about the contact mechanism of pathogenic virus transmission from person to person. Probably, the causes of the pandemic are related to global changes in the biosphere of the planet. According to V. I. Vernadsky's theory, the biosphere consists of three main parts: plants, animals and microorganisms, the total mass of which is a constant value. In recent decades, the rate of destruction of forests as the main resource of the plant world has considerably increased. The number of wild animals has decreased and at the same time the human population has increased. The growing disproportions led to the expansion of viruses with a new vector from animals to humans. Global insight into the role of viruses in the biosphere of the planet leads to understanding of the COVID-19 pandemic causes. There is every reason to believe that viruses have wave properties, and are able to produce a magnetic field, stable coherent resonance systems and interact without the participation of biochemical transformations. The energy of the electromagnetic field can be high enough for non-contact infection and assembly of an active biological virus inside the human body. The physical theory of viruses significantly expands the existing understanding of the role of viruses in the biosphere of the planet and the causes of new viral infections.

Plasma virome and the risk of blood-borne infection in persons with substance use disorder

There is an urgent need for innovative methods to reduce transmission of bloodborne pathogens like HIV and HCV among people who inject drugs (PWID). We investigate if PWID who acquire non-pathogenic bloodborne viruses like anelloviruses and pegiviruses might be at greater risk of acquiring a bloodborne pathogen. PWID who later acquire HCV accumulate more non-pathogenic viruses in plasma than matched controls who do not acquire HCV infection. Additionally, phylogenetic analysis of those non-pathogenic virus sequences reveals drug use networks. Here we find first in Baltimore and confirm in San Francisco that the accumulation of non-pathogenic viruses in PWID is a harbinger for subsequent acquisition of pathogenic viruses, knowledge that may guide the prioritization of the public health resources to combat HIV and HCV.

Molecular Mechanisms of Possible Action of Phenolic Compounds in COVID-19 Protection and Prevention

The worldwide outbreak of COVID-19 was caused by a pathogenic virus called Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). Therapies against SARS-CoV-2 target the virus or human cells or the immune system. However, therapies based on specific antibodies, such as vaccines and monoclonal antibodies, may become inefficient enough when the virus changes its antigenicity due to mutations. Polyphenols are the major class of bioactive compounds in nature, exerting diverse health effects based on their direct antioxidant activity and their effects in the modulation of intracellular signaling. There are currently numerous clinical trials investigating the effects of polyphenols in prophylaxis and the treatment of COVID-19, from symptomatic, via moderate and severe COVID-19 treatment, to anti-fibrotic treatment in discharged COVID-19 patients. Antiviral activities of polyphenols and their impact on immune system modulation could serve as a solid basis for developing polyphenol-based natural approaches for preventing and treating COVID-19.

Identification of Potential Scaffolds From the Shrub Justicia Adhatoda Against SARS-CoV-2 Main Protease Target

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a highly infectious and pathogenic virus. To date, there is a lack of proper medication against this virus, which has triggered the scientific community to find therapeutics. Searching of SARS-CoV-2 main protease inhibitors from anti-viral natural products based on traditional knowledge may be an effective approach. In this work, structure-based virtual screening of the compounds of Justicia adhatoda was performed against SARS-CoV-2 Mpro, followed by ADME filtration, molecular dynamics, and MMGBSA-based binding free energy calculation. On the basis of docking score, crucial interacting amino acid residues, molecular dynamics, and binding energy profile, three novel phenolic compounds JA_38b, JA_38c, and JA_39 were selected as potential binders against SARS-CoV-2 Mpro. This information may be used to develop potential therapeutics countermeasures against SARS-CoV-2 infection after in vitro and detailed pharmacological study.